Profile grinder



Sept. 11, 1934. c. Ross PROFILE'GRINDER Filed Dec. 9. 1930 5 Sheets-Sheet l gnwwtoc (ma/arm L/E'ass Sept. 11, 1934. Ros 1,973,508

PROFI LE GR I NDER Patented Sept. 11, 1934 PATENT OFFlCE PROFILE GRINDER Charles L. Ross, Washington, D. (l.v Application December 9, 1930, Serial No. i,155

21 Claims.

The invention relates to profiling machines for the generation of curved or warped surfaces, and more particularly has reference to a mechanism for carrying the work undergoing finishing.

Many metal articles or devices are, at the present; initially formed by forging or casting, and are subsequently ground or cut to bring them to the shape and dimensions required by speciiications for the particular object. In general, it two methods of finishing are employed, either by hand finishing or by the use of a rotating cutter or grinding tool which is movedon the work. Where the metal being finished has a contour of a curved or warped surface, practice such as that id outlined above, results in inaccurate work in that the surface of the finished piece possesses relatively high and low spots. These defects in the finished casting cause either a lowering of the efliciency of the casting itself, or the machine, device, or structure with which it is associated.

Particularly is this inaccuracy of the surface encountered in the grinding or cutting of curved or warped surfaces, such for example, as those encountered in the formation of screw propellers. 25 The form or shape of a propeller is usually considered to be based upon a helicoidal surface, and

whilethe shape of a helix may be inscribed upon paper with the aid of a plan and end view of a cylinder, and the methematical' equation thereso iore may be derived, it has been impossible to finish the propeller so that it even approximately 4 measures up to its specifications, within tolerances usual in machine tool work.

The major object of this invention is theprovision of a machine which enables the work to be produced within the tolerances usual to the product of machine tools.

An equally important object of the invention is the provision 0i-a headstock for a profiling machine in which the work being machined is moved longitudinally with or in relation to the headstock, either towards the forward or rearward end of the same, so that either movement of the work in either direction, brings it past a tool maintained in a fixed position. v

Another object of the invention is the, provision of a novel thrust torque drive for the ram of a profiler.

Still another object of the invention is the provision in' a headstock of a profiler having a thrust torque drive-of means for unbalancing the machine and causing the longitudinal and rotative movements of the work carrying arbor. to begoverned by one template of desired form, to the end that the shape of the work on the arbor is not controlled by the movement of a plurality of grinding members, thereby aiding in the elimination of back lash.

Yet another object of the invention is the provision in a profiler of means for automatically preventing back lash.

A further object of the invention is the provision of a profiler machine of simple design, capable of finishing an article having any shape and possessing either a straight or a curved surface. 35

With these and other objects in view, which may be incident to my improvements, the invention consists in the parts and combinations to be hereinafter set forth and claimed, with the understanding that the several necessary elements comprising my invention may be varied in construction, proportions and arrangement without departing from the spirit of the invention and scope'of the appended claims.

The invention comprehends the provision of a W profiler machine which may be used in the finishing of castings and the like, having any type of surface. More particularly the present inven-, tion relatesto the headstock of such a machine which is so constructed that it carries and moves 0 the work being finished past a grinder or cutter which is held in a fixed position. One manner of practically carrying the invention into efiect is to couple an arbor carrying the work being machined to a spindle on a headstock.

The spindle, just mentioned, is rotated as well as moved laterally by means of a novel thrust torque drive. By connecting the spindle to a follower arm adapted to follow a former or template and unbalancing the spindle, the work may to be so moved that a rotating tool mounted upon a stationary base will evenly move over the surface to be finished. Not only does the invention contemplate working the rough casting or other article as it moves across the tool in one direction, but includes working it upon the direction of movement of the headstock being reversed.

In order to make my invention more clearly understood, I have shown in the accompanying drawings, means for carrying the same into practical eflect without limiting theimprovements in their useful applications to the particular constructions which, for the purpose of explanation,'have been made the subject of illustration.

, In the drawings:

Figure 1 is a plan view of the headstock of a profile grinder forming the subject matter of the invention.

Figure 2 discloses a side elevation of the machine shown in Figure 1.

Figure 3 is a vertical sectional view along the line 3-3 of Figure 1.

Figure 4 is a vertical section on the line 4--4 of Figure 3, and discloses the means for coupling 'the drive mechanism to the device.

Figure '7 is a detailed end elevation of the counter balance mechanism used with the machine.

Throughout the drawings, similar reference numerals refer to like parts in the difierent views. There is shown in Figure 1, a headstock of a profller and a portion of the work arbor secured thereto. The tailstock of the machine, as well as the tool, both of which are positioned to the right of the headstock, have for the sake of simplicity, been omitted from the drawings.

'As may be noted, the headstock comprises a pedestal 1, which is secured to a suitable bed plate by any conventional means, such as the anchor bolts 2, provided in the base of the pedestal. On one side, the top of the pedestal, (Figures 5 and 6) is provided with projection. 3, which extends for substantially the full length of the pedestal. The projection 3 is provided wi-.h a V-shaped groove 4 which cooperates with a gib 5 upon the other side of the pedestal to form a slideway for a pitch saddle. Gib 5 is maintained in position by a gib retaining bar 6, secured to the pedestal at suitable intervals by bolts 7. The gib bar 6 is provided with adjusting screws 8 for adjusting the gib 5 as desired.

In the slideway 9 of the pedestal between the groove 4 and the gib 5, there is adapted to be positioned a pitch saddle 10 provided with a suitable base or supporting members 11 which cooperate withthe V-shaped groove 4 and the gib 5. The pitch saddle 10, as may be noted, is thus slidably mounted upon the pedestal to accommodate the mechanism for varying conditions of operation.

' As its name implies, the pitch saddle 10 is provided with a saddle-like supporting member 12, having a boss 13 which is provided with the internal bore 14. Mounted upon the pedestal 1, in alignment with the bore 14, is a bracket 15 adapted to support a screw threaded shaft 16 in the bearing 1'7. The shaft' 16 extends through the bearingl'l, and through a screw threaded plate 18,secured to the pitch saddle, and into the bore 14.

\ Upon the side of the bracket 15 most distant from the pedestal of the headstock, there is provided a suitable actuating handle 19 for rotating the threadd shaft 16, and adjacent this side of the pedestal a graduated wheel 20, which cooperates with the pointer 21 secured to the bracket. It is thus evident that the pitch saddle may be positioned upon the pedestal as desired by the actuntion of the handle 19, the position. pf the saddle being determined by the scale wheel 20, cooperating with the pointer 21. r

For the purpose of maintaining the pitch saddle in adjusted positions, a locking member 22 is positioned over the gib retaining bar 6 so that one of its inner ends engages: a slot 23 in the side of one of the uprights 10' of the pitch saddle. The locking member 22 is mounted upon a stud 24, which is provided with a nut in the form of 41 for supporting a hollow spindle 42. .be noted, the end of thev spindle most distant ram, generally designated by the reference nu-v meral 26 is positioned upon the pitch saddle itself. To accomplish this, the upper ends of the uprights 10' of ,the pitch saddle are provided with gib retaining plates 2'7 secured thereto by bolts 28 in order that gibs 29 may be held against the sides of the ram, and provide a slideway therefor. For wear take-up-purposes, the gibs 29 are provided with adjustment screws 30 at suitable intervals. 7

As may be observed in Figures 1 and 2, there is secured to the pitch saddle, suitable plates 31, to each of which is connected one end of a tie rod 32, the other end of each tie rod supporting a cross piece 33 to which is attached a cylinder 34. The cylinder 34 is provided with a piston 35 and piston rod 36, the latter extending through the .plate 33 in such a manner as to be freely slidable therethrough. {it its free end the piston rod 36 is secured, in any conventional manner, to a yoke 37' formed on an actuator member-3'7. A main yoke 51 is formed upon the actuator 37 in order that it may be supported, for a reason presently to appear,upon a spindle which iscarried by the ram. As may be noted, in Figures 1 and 5, the actuator member is provided with arms 37" of rectangular cross section which extend over ribs 26' on the ram so as to have a slight clearance between these members. The

ribs 26 are positioned longitudinally of the ram and are substantially equal to the length thereof By reason of the foregoing construction, it is evident that upon actuation of the piston 35,

into which are seated suitable bearings 40 and As may from the actuating cylinder is provided with an annular extension forming a bearing plate 43 which abuts the end of the bushing 41. Outside of the bearing plate 43, the spindle is screw threaded, as at 44, the purpose of which will be hereinafter set forth.

Thespindle 42 is of such length that it extends to the rear of the ram and through the-bushing 38 for a considerable distance. Suitable thrust bearings 89 of the ball bearing type, are employed with the spindle 42, and are maintained against the bearing supports 38 and 39 and the bearings 40 and 41 by the use of collars 90 provided with suitable means adapted to engage the spindle, such as the set screws 91. In some instances it may be found desirable to thread the spindle as noted by the reference numeral 45 so as to receive a lock nut 46 contact with the bearing 40. By these means the spindle is maintained. in its bearing so that no longitudinal movement of it is allowed, while at the same time it may be rotated.

As already pointed out, the spindle 42 is of is adapted to be engaged by the screw threaded end of a draw bar 49 which passes entirely through the spindle and extends beyond its end adjacent the actuating cylinder.

For the purpose of preventing relative rotation ofthe collet with respect to the draw bar, the former is provided with a key way into which is setthe end of the guide screw50 which is held in place by any well known means, such as the head of the retaining screw 50' abutting the head of the guide screw.

It will hence be apparent that by suitably rotating the. draw bar the collet will be forced outwardly so that the arbor 48 may be removed therefrom or inserted therein, while rotation of the draw bar in the opposite direction will pull the collet inwardly toward the ram piece and firmly lock it and the arbor to the spindle so that rotation of the latter will be transmitted to the arbor.

In Figures 1 through 5, particularly well shown is the novel means which I have devised for coupling the-thrust energy of the piston rod 36 to the spindle so that a thrust torque drive for the latter is provided. This actuating mechanism consists of the actuating member 3'7 provided with theyoke 51 which extends between its sides and may be formed integral-therewith. The yoke 51 is bored to receive a collar 52 which is secured thereto by any suitable means such, for example, as the set screws 53. As may be noted in Figures 3 and 4, the collar 52 is provided with a slot 54 formed on the periphery thereof and entirely extending through the collar. This opening or slot 54 is in the form of a helix and is angularly positioned with respect to the axis of the collar.

As already pointed out, the spindle 42 extends for a considerable distance beyond the bushing 40,-and it is of a sufiicient length so that its end adjacent to the bushing will extend into the collar 52 ,which is provided with an internal diameter adapted to receive the spindle. Secured to the spindle is a screw 55 having an annular head over which is positioned a roller 56. The screw and roller are engaged by the sides of the slot 54. Hence, it will be apparent that longitudinal movement of the actuator yoke will impart a rotating movement to the spindle.

Assume, for example, that the piston 35.is so actuated that it is pushed towards the right, as viewed in Figural. This movement of the'piston 35 results in moving the actuator yoke forward and hence the spindle 42 upon which it is mounted, with the result that the ram is moved forwardly since the spindle is securely carried thereby. At the same time, the movement just described, because of the slot 54, willtend to move the screw and roller secured to the spindle downwardly, which results in rotating the spindle in.a clockwise direction, as viewed in Figure 6. By suitably choosing the angular position of the slot 54, force from the piston and piston rod is translated into equal components of thrust and torque, the former giving longitudinal movement to the ram piece, while the latter impartsrotative movement to the spindle.

As may be observed in Figure 4, the draw bar extends within the actuator yoke and collar, and

as shown in Figure 3, continues through these members. Slipped over this end of the draw bar shaft is a sleeve 57, one end of which abuts the end of the spindle within the actuator collart' The sleeve 57 is secured to the draw bar in any conventional manner, and is provided at its end nearest the actuating cylinder with a plurality of holes or openings 58 adapted to receive a tool for rotating the draw bar and hence adjusting the position of the collet 4'1.-

- In the parts of the machine heretofore described, the driving mechanism for the ram piece and the spindle has been considered. It should be noted that these parts of the driving mechanismare floated, and that the torque developed therein is balanced by the thrust. With such an arrangement, it would be impossible to finish a curved and warped surface by passing it across the face of a cutting or grinding tool. To accomplish this, however, a hood 59, having a semi-circular cross section is positioned over the ram piece and secured to the edges of the pitch saddle by any conventional means, such for example, as the angle irons 60 and 61 and cooperatthe side of the opening 63 opposite to the template, there is detachably secured a master plate .87 which is employed, in a manner to be hereinafter pointed out, for setting the template.

As will be presently pointed out,'the template 64 cooperates with a pitch operating or follower arm so as to determine the longitudinal and the rotative movement of the spindle carrying the work arbor. the reference'numeral 66. The pitch operating arm 66 is mounted upon the spindle 42 and is secured thereto in any conventional manner, so

as to rotate therewith. It may be noted, the

pitch operating arm is adapted to extend through the slot 63 in the hood. Near the point where it passes therethrough, there is provided a base portion 67 with the bifurcated uprights or arms 68, the upper ends of which are joined by cross pieces 69. p

The frame formed by the uprights and cross pieces just described, is adapted to support roller pivot rods 70, the lower ends of which are provided with eyes adapted to have pivot pins 71 pass therethrough. Pivot pins 71 are supported in the base portion 67 adjacent the lower ends of the uprights, and are maintained therein by any conventional means, such for example, as cotters. Each roller pivot rod is provided at a point near the edge of the template with a bearing surface 72, adapted to support the cam rollers 73, the end of .the pivot roller shaft extending through the rollers themselves. At its upperend the pivot Such a .follower arm is denoted by i theoretical finished casting. Upon the hood on roller-shaft is screw threaded so as to receive a nut 74 adapted to hold the guide roller thereon, and is extended above the threads so as to form an eye.

The upper eye in each roller pivot rod is engaged by the bifurcated ends of aroller adjusting rod '75, which is secured thereto by pivot pin 76. Between the cross pieces, at the head or upper end of the frame on the pitch operating arm, there is provided a suitable bearing piece '17 adapted to receive the ends of the roller pivot shafts '75 in elongated or slot-like openings. Wedges 79 are positioned about the upper end of each roller pivot rod through the ends of the slotlike opening just mentioned.

By the use of the wedges, the cam rollers may be adjusted so that they are in contact with the template. While two cam rollers have been disclosed and only one template, which requires only one roller, it should be noted'that a second template can be placed upon the left side of the slotted opening 63, as shown in Figure 1. As will be hereinafter pointed out, a second template may be used for finishing the reverse side of the casting from that which is ground or cut through the aid of the template on the right. However, for the sake of simplicity, a second template has been omitted from the drawings, and when used it func-. tions in a similar manner to that shown, using a cam roller on the left, as disclosed in Figure 3.

To still maintain the device in a floating condition, such as that described, there is mounted upon the threaded end of the spindle a weight wheel 80. The wheel 80 is provided with threads which cooperate with threads 44 so that the same may be secured to the spindle; Carried upon weight wheel 80 is a counter balance weight 81 adapted to ofiset the eccentric weight upon the spindle due to the pitch operating or follower arm. As may be observed, the counter balance 81 is secured to the weight wheel by means of the bolts 82, and by the use of a slot 83 formed the counterbalance, adiustment of the same may be made if desired.

The parts previously described do not function to maintain the cam rollers of the pitch operating arm against the former or template. In accomplishing this so that the longitudinal and the rotative movement of the spindle may be such as to follow the template without backlash, a counterweight 84 is suspended over the rim of the weight wheel 80 by means of a cable 85 secured to the weight wheel in any well known manner, at 86. As may be observed, the counterweight 84 places a constant torque on the spindle, and not only maintains the pitch operating arm against the template, but prevents backlash, and also allows the work to stop at the same position upon the end of a particular stroke.

These conditions, just mentioned above, may best be noted by a consideration of the operating principle of the device.

A template 64 is first set up upon the hood of the machine at its proper angle, through the use of the master plate 8'7. This template is made by a suitable development from the working drawings of thepiece or article to be machined. The work to be finished is set upon the arbor in the usual manner, and in instances where it is relatively heavy and of a considerable size, a tailstock, mentioned in connection with the drawings but now shown, is employed to support the arbor 48. Assume that the casting being finished is a screw propeller. Its hub is slipped over the arbor 48, which has been previously secured to the spindle by means of the collet, after which a sleeve is put over the arbor so as to be flush with the hub of the propeller, and the tailstock is brought into the proper position for supporting the arbor.

The cutting or grinding tool is in a fixed position at right angles to the arbor shaft, its position being changed for each cut or stroke'of the piston. Whilenot shown in the drawings. it should be noted that during the cutting stroke the tool is fixed and its position is changed between strokes of the ram. During the operation of the device, movement of the ram carries the work past the tool irrespective of whether the ram is moved towards the tailstock or away from it.

The work, having been placed upon the arbor as described, thepitch saddle is adjusted to the desired position by releasing the locking handle 25 and rotating the actuating handle 19 so as to move the pitch saddle to a point desired, as indicated upon the scale wheel 20 by means of the pointer 21. The pitch saddle having been suitably positioned, it is again locked in place by the handle 25.

As previously described, upon movement of the piston 35 towards the right of Figure l, the ram also moves to the right, and the spindle 42 is rotated in a clockwise direction when moved towards the tailstock of the device. It has been explained that the force created by the actuation of the piston 35 is broken into equal components of torque and thrust at the actuator yoke.

For the moment, considering that the counterweight 84 is not connected to the machine, it will be appreciated that the movement of the pitch operating arm will be of a similar degree as that of the spindle so that if the motion of the cam roller were projected upon a vertical plane, perpendicular to the longitudinal axis of the spindle, an arc of a circle would be described. Obviously, since the surface being finished is of a curved nature, or it might even be a warped surface, this condition is not desired; To obviate this, .the counterweight 84 is hung upon a weight wheel.

The result of this expedient is to put a constant and independent torque upon the spindle which will cause a cam roller to be in constant contact with'the template or former. A similar result would be obtained by securing a spring to the pitch operating arm and to any stationary part of the machine. This practice may be followed iidesired, but I prefer the use of a counterweight and weight wheel, suchas that disclosed for unbalancing the machine.

The independent torque on the spindle caused by the counterweight 84 hence results in breaking up the thrust and torque imparted to the spindle through the actuator so that either one 01 these forces is limited while the other is increased to allow the pitch operating arm and its cam roller to follow the template. It has been pointed out, there is a small clearance between the actuator arms 3'7 and the ribs 26' formed upon the ram 26. The purpose of this construction. having considered the limitation of the longitudinal and rotative movement of the spindle caused by the counterweight 84, will now be apparent. If the actuator arms rested firmly on the ribs 26, the limitation of the movements of the spindle due to the follower arm being in contact with the former would result in binding the roller 55 in the slot 54 of the actuator collar. Hence a slight amount of play is allowed the actuator collar by providing the small clearance .between the actuator arms and the ribs on the ram piece. Obviously, the amount of this play is limited by the amount of clearance between the actuator arm and the ribs just mentloned. 1 Movement of the ram to the right or towards the tailstock has been considered. It is obvious that its movement away from the tailstock will cause the work to be drawn across the cutting or grinding tool in the opposite direction. At the same time the constant torque upon the spindle created by the counterweight 84 will cause the cam roller of the pitch operating arm to follow its template. It will thus be appreciated that cutting or grinding may be carried on upon movement of the ram in either direction.

Another important function of the counterweight resides in the fact that because of the independent torque created by it upon the spindle, backlash in the machine is prevented. This, of course, means that in making a new cut or finishing an old cut at the beginning of the piston stroke, the cutter will not dig into the casting and leave a relatively low spot at the beginning of the path or section being machined. The delicateness and the accuracy of the adjustment bepleted its stroke, say for example, towards the.

tailstock of the profile grinder, the work or casting will be in the same position with respect to the axis of the spindle. This same relation exists when the ram is in its position nearest the actuating cylinder. As is well known. such a condition is of considerable aid in preventing the breakage of tools.

In the description heretofore given, it has been assumed that the template has been properly set upon the hood of the machine. The follower arm will constantly be in contact with the template 64 and thus rotate and move the work longitudinally the correct amount. It is essential, however, that the template be positioned at the desired angle calculated to effect movement of the work arbor a predetermined amount.

Again assuming for illustrative purposes, that a propeller is to be machined, it will be noted that the form and shape thereof is usually considered to be based upon a helicoidal surface. The lead or pitch of a propeller blade would be the distance that a point on the blade would move forward for one revolution of the blade. Assume a cylinder of revolution with a helix passing around the same. It is evident from the above that the lead of the helix and radius of the cylinder being known, that the helix angle may be calculated, its tangent being equal to the dividend of the lead of the helix divided by the circumference of the cylinder.

By an inspection of Figure 1 and. especially Figure 6, it will be appreciated that the radius of the outer surface of the hood 59' is known, the center of the spindle being the center of the semicylindrical hood. Hence, with the radius of the hood known, the circumference of a complete cylinder may be calculated, and since by the design of the propeller, its lead is known, the helix angle may be calculated in a manner similar to that noted above so that the template may be.

- suitably set.

means the template may be set at its proper angle. It will hence be appreciated that by reason of the template, the follower arm will be caused to move the work as previously described in the desired manner.

If it is desired to finish the other face of the casting with a different form from that finished by the use of the template 64, a second template for the reverse face is employed. This second template is set in a manner similar to that already described and is secured upon the actuating cylinder side of the slot 63 in the hood 59, and the counterweight is moved so that it is on the opposite side of the spindle axis from that shown in Figure 1. When such practice is followed it will be appreciated that the device operates in a manner like that previously, described.

It is to be noted, however, that with the use of two templates where the casting is to be finished on two faces, the necessity of reversing it upon the arbor is avoided.

While I have disclosed a machine for finishing curved surfaces and specific mention has been made to propellers, it is to be understood that the device is in noways limited to pieces of this nature, for obviously pieces having curved surfaces and used for other purposes can easily be finished upon the machine without departing from the spirit of the invention and the scope of the claims appended hereto.

With the machine which I have described, it is possible to accomplish very accurate work which measures up strictly with the specifications. This fact will be appreciated due to the fluid pressure thrust torque drive of the device eliminating lost motion, the steady torque thrust drive, and the prevention of backlash by the counterweight mechanism.

From the foregoing description it will be appreciated that I have devised a novel headstock for a profile grinder which is of simple construc- A tion giving rise to ease of operation. By providingan unbalanced thrust torque drive, it is possible to cause an operating arm to follow a template of any shape necessary to move the work, having a curved surface, regularly and evenly across a cutting and grinding tool. To be further appreciated is the fact that in the device backlash is eliminated and that the machine may i ferred embodiment-of my invention, I wish it to' be understood that I do not confine myself to the precise details of construction herein set forth, by way of illustration, as it is. apparent that many changes and variations may be madev therein, by those skilled in the art, without departing from the spirit of the invention, or exceeding the scope of the appended claims.

I claim: v

1. In a profile grinder, a headstock mechanism comprising a pedestal, a ram slidable Iongitudinally thereof, a spindle rotatively mounted 3/ on said ram in a fixed longitudinal relation thereto, a work arbor secured to the spindle, an actuator member provided with 'a yoke for receiving an end of the spindle, means for moving said actuator member longitudinally of the spindle, means for coupling said actuator yoke to the spindle so as to impart longitudinal and rotative movement thereto, and other means for limiting the longitudinal and rotative movement of the spindle as desired.

2. In a profile grinder, a headstock mechanism comprising a pedestal, a ram slidable longitudinally thereof, a spindle rotatively mounted on said ram in fixed longitudinal relation thereto, a pitch operating arm secured to said spindle, a work arbor detachably connected to said spindle, an actuator member provided with a yoke for receiving an end of the spindle, means for moving said actuator member longitudinally of the spindle, means for coupling said actuator yoke to the spindle so as to impart longitudinal and rotative movement thereto, and other means for causing the pitch operating arm to follow a predetermined outline so as to limit the longitudinal and rotative movement of the spindle.

3. In a profile grinder, a headstock mechanism comprising a pedestal, a ram slidable longitudinally thereof, a spindle mounted on said ram in fixed longitudinal relation thereto, a work arbor connected to the spindle, a pitch operating arm secured to the spindle and adapted to follow a template associated with the headstock mechanism, an actuator member provided with a yoke for receiving an end of the spindle, means for moving said actuator member longitudinally of the spindle, means for coupling said actuator yoke to the spindle so as to impart longitudinal and rotative movement thereto, and other means for causing the pitch operating arm to follow the template so as to control the longitudinal and rotative movement of the spindle as desired.

4. In a profile grinder, a headstock mechanism comprising a pedestal, a ram slidable longitudinally thereof, a spindle mounted on said ram in fixed longitudinal relation thereto, a work arbor connected to the spindle, a pitch operating arm secured to the spindle, said pitch operating arm adapted to follow a template associated with the headstock mechanism, a wheel fixed to one end of said spindle, an actuator member provided with a yoke for receiving the other end of the spindle, means for moving said actuator member longitudinally of the spindle, means for coupling said actuator yoke to the spindle so as to impart longitudinal and rotative movement .thereto, and other means associated with said wheel so as to place an independent torque on the spindle for maintaining the pitch operating arm in constant contact with said template and controlling the longitudinal and rotative movement of the spindle.

5. In a profile grinder, a headstock mechanism comprising a pedestal, a ram slidable longitudinally thereof, a spindle mounted on said ram in fixed longitudinal relation thereto, a work arbor connected to the spindle, a pitch operating arm secured to the spindle, said pitch operating arm adapted to follow a template associated with the headstock mechanism, awheel fixed to one end of said spindle, an actuator member provided with a yoke for receiving the other end of the spindle, means for moving said actuator member longitudinally of the spindle, means for coupling said actuator yoke to the spindle so as to impart longitudinal and rotative movement thereto, and a weight connected to the periphcry of said wheel for imparting an independent torque upon the spindle.

6. In a profile grinder, a headstock mechanism comprising a pedestal, a ram slidable longitudinally thereof, a spindle mounted. on said ram in fixed longitudinal relation thereto, a work arbor connected to the spindle, a pitch operating arm secured to the spindle, said pitch operating arm adapted to follow a template associated with the headstock mechanism, a wheel fixed to one end of said spindle, an actuator member provided with a yoke for receiving the other end of the spindle, means for moving said actuator member longitudinally of the spindle, means for coupling said actuator yoke to the spindle so as to impart longitudinal and rotative movement thereto, and a weight connected by a cable running over the periphery of said wheel and secured thereto so as to impart an independent torque upon said spindle.

'7. In a profile grinder, a headstock mechanism comprising a pedestal, a ram slidable longitudinally thereof, a spindle rotatively mounted on said ram and fixed in longitudinal relation thereto, a hood positioned upon the headstock mechanism adapted to be adjusted with respect to the pedestal, said hood being provided with a slot,- a template positioned adjacent said slot, a work arbor connected to said spindle, means for imparting longitudinal and rotative. movement to said spindle, and means connected to said spindle and cooperating with said template for controlling the longitudinal and rotative movement of the spindle.

8. In a profile grinder, a headstock mechanism comprising a pedestal, a ram slidable longitudinally thereof, a hood positioned over the ram, means for adjusting theposition of the hood and maintaining it in a fixed position with respect to the pedestal, a spindle rotatively mounted on said ram and fixed in longitudinal relation thereto, a work arbor connected to said spindle, said 'hood being provided with a slot adapted to have a pitch operating arm secured to said spindle extend therethrough, a template adjacent one side of said .slot, means. for imparting longitudinal and rotative movement to said spindle, and means for maintaining said pitch operating arm in contact with said template so as to control the longitudinal and rotative movement of the spindle.

9. A thrust torque drive adapted to impart a longitudinal and rotative movement to a work carrying arbor of the headstock of a profile grinder comprising. a spindle carried by a ram, said ram being slidable longitudinally of the pedestal of said headstock, an actuator member provided with a yoke, a collar secured'to said yoke, an end of said spindle adapted to be received in said collar, means for imparting movement to said actuator member longitudinally of said machine, and means for coupling said collar to said spindle so as to impart a longitudinal and rotative movement to the spindle.

10. A thrust torque drive for the headstock of a profile grinder, said driveincluding a spindle, rotatively mounted upon a ram slidable longitudi-' nally of the headstock, an actuator member floated upon said spindle, said actuator member provided with a yoke, a collar secured therein, said collar being provided with a slot, an end of the spindle adapted to extend within said collar, coupling means upon the spindle adapted to be engaged by said slot, and means for imparting a thrusting force to said actuator member longitudinally of the headstock, said thrust being translated by said slot and coupling into rotative and longitudinal movement of the spindle.

11. A thrust torque drive for a headstock oi a profile grinder, said drive including a spindle ro-, tativeiy mounted upon a ram slidable longitudl-.

headstock.

'nally of the headstock, an actuator member pro vided with a yoke connected to said spindle through a collar, said collar being secured within said yoke and provided with a slot adapted to engage coupling means on the spindle, means for imparting a thrusting force to said actuator member longitudinally of the headstock, said force being translated by said slot and coupling into a rotative and longitudinal movement of the spindle, means for controlling the rotative and longitudinal movement of said spindle, and means for preventing the binding of said coupling in the slot of said collar.

12. In a profile grinder, a headstock mechanism comprising a pedestal, a ram slidable longitudi nally thereof, a spindle rotatively mounted on said ram in fixed longitudinal relation thereto, a work arbor connected to the spindle, an actuator member connected to said spindle, means for imparting a thrusting force to said actuator longitudinally of the pedestal, means for translating said force into components of thrust and torque to be applied equally upon the spindle, and other means for unbalancing said spindle so as to limit the longitudinal and rotative movement thereof as desired,

13. In a profile grinder a headstock mechanism comprising a pedestal, a pitch saddle adjustably mounted thereon, a ram slidably mounted upon said pitch saddle, a spindle rotatively mountedon said pitch saddle in longitudinalfixed relation thereto, a fluid pressure actuated cylinder with piston supported by said pitch saddle, a piston rod for said piston connected to an actuator member so asto impart longitudinal-movement thereto, said actuator member being provided with a yoke adapted to receive an end of i said spindle, and means for coupling said spindle to said actuator member so that the thrust of the actuator member is translated into equal components of thrust and torque on the spindle.

14. In a profile grinder a headstock therefor, comprising a pedestal, a ram slidable longitudinally of said pedestal, a spindle rotatively mounted upon said ram in fixed longitudinal relation thereto, a template adjustable with respect to said pedestal positioned upon said headstock mechanism, means for imparting longitudinal and rotative movement to said spindle, and means cooperating with said template and said spindle for controlling the longitudinal and rotative movement of said spindle when the spindle is moved longitudinally towards either end of the 15. In a profile grinder a headstock mechanism therefor comprising a pedestal, a ram slidable longitudinally thereof, a spindle rotatively mounted on said ram in fixed longitudinalv relation thereto, means for imparting longitudinal movement to the ram and spindle and rotative movement to the spindle, a template positioned upon said headstock in adjustable relation with respect to the pedestal, a pitch operating arm secured to said spindle andadapted to cooperate with said template for controlling longitudinal and rotative .movement of said spindle, and means for causing the pitch operating arm to follow said template when the spindle is moved longitudinally towards either end of said headstock.

16. A method of setting a template for controlling the movement of a piece of work carried by a headstock mechanism of a profller, said headstock mechanism having a .work carrying spindle, the longitudinal and rotative movement thereof being determined by a follower arm secured thereto and adapted to cooperate with a template placed upon a semi-cylindrical hood positioned over the mechanism, said hood having also placed thereon a master plate, the edge thereof nearest the template being at a known angular relation with respect to the cylindrical hood, comprising the steps of determining the angular relationship between the template and said hood so as to give the desired movement to the spindle, calculating the distance between a number'of points on the template and a number of opposite points on the master plate for the determined angular position of the template, setting the template upon the hood, and adjusting its distance from the master plate in accordance with the distances calculated. 7

17. In a machine for machining curved surfaces, an arbor, means for delivering rotative and longitudinal movement to said arbor, separate means cooperating with the first mentioned means for accurately guiding the rotative and longitudinal movement of said arbor, and biasing means holding said arbor against said guiding means.

18. In a machine for machining curved surfaces, an arbor, means for delivering rotative and reciprocating movement to said arbor comprising driving and driven parts, separate means having driving and driven parts guiding the arbor in its rotative and reciprocating movements said means having a greater relative movement between the driving and the driven parts than the first means, and biasing means holding said arbor against said guiding means in both directions of its reciprocating movement.

19. In a machine formachining curved surfaces. an arbor, means for delivering rotative and longitudinal movement to said arbor comprising driving and driven members and means for controlling the rotative and longitudinal movement of said arbor, comprising a guiding surface 00.- operat-ing with a part moving with said arbor, the motion between the guiding surface and said part being greater than between the driving and driven members.

20. In a machine for machining curved surfaces, an arbor, means for delivering rotative and reciprocating movement to said arbor comprising driving and driven members and means for controlling the rotative and reciprocating movement of said arbor, comprising a part moving with said arbor and a guiding surface against which said part bears in both directions of its reciprocating movement, the motion between the guiding surface and said part being greater than between the driving and driven members.

21. In a machine'for machining curved surfaces, an arbor, means for delivering rotative and longitudinal movement to said arbor permitting play between the moving parts, means for accurately controlling the rotative and longitudinal movement of said arbor, comprising a guiding surfacecooperating with a part movingwith said arbor and biasing means holding said part-against said surface.

CHARLES L. ROSS. 

